Parts tty_

(1)

F86 Class Schedule

Day 1 Day 2 Day 3

OVERVIEW ADVANCED MCS FNP INTERNALS

USAGE Morning

General Telecomm tty_ Programs and

Concepts TTF Databases

MCS Parts

FNP Description

MCS RING 0 MCS MCS METERING

ADMINISTRATION INTERNALS AND DEBUGGING

After-

noon CMF Programs and Ring 0 MCS Meters

FNP Core Image Databases FNP Meters Operator Commands Multics-FNP debug_fnp

Dialogue Dump Analysis

Tools

(2)

MCS Overview

& What is MCS

Multics Communications System

Software to transfer data to/from terminals or other devices connected via communications lines

Sometimes called MCM: Multics Communications Manager Design is generalized, table-driven

Especially good at supporting diverse asynchronous terminals In this course most of the major MCS topics are covered

Administration

CMF, TTF, FNP images Use

All Ring 0 interfaces to MCS functions Internals

I Ring 0 and FNP

Metering and Debugging Ring 0 and FNP

There are certain topics within MCS or related to MCS that will not be covered in detail

Details of various protocols i HASP, X.2S, etc.

Video System

I/O Daemon software

FNPs other than 355/6670 families

wnat

^{is MCS}

F86 Page 1-1

(3)

a Standard Communications Concepts

Some communications concepts that are not necessarily specific to Multics need to be understood in order to understand MCS.

ASCII Character Set

Multics was one of the first systems to use ASCII standard Character sizes

128 7~bit characters defined by standard Usually transmitted as 8-bit characters

I

7 data bits plus 1 parity bit Stored in 9-bit bytes in Multics

I 7 data bits plus 2 zero bits

Standard Communications Concepts

MCS Overview F86 Page 1-2

(4)

7-bit Character 7 6 5 4 3 2 I D

1

^D

1

^DID

1

^DÎ^DÎ^DÎ

a

1

a I a I a

1

a

1

a

1

a

1

t

1

^t I t I t

I

^t I t I t

I

a I a I a I a I a I a I a I

1 1 1 1 1 1 1

I

1

I I

1 1 1

I

1---1---1---1---1---1---1---1

7-bit Character Plus Parity Bit 8 7 6 5 4 3 2 1 p D D

1

^D

1

D

1

^DI ^DI ^DI a a a I ^a

1

^a

1

^a I ^a

1

^a

1

r t t

1

^t ^I ^t ^I ^t

1

^t ^I ^t

1

i a a

1

^a

1

a

1

^a

1

^a

1

^a

1

t I

1 1

I I I

I y I I I

1 1

I I I

1---1---1---1---1---1---1---1_1

7-bit Character Stored in 9-bit Byte

9 8 7 6 5 4 3 2 1

I ^D

1

^D

1

^DI ^D

1

^D

1

^D

1

^D

1

I â Î â

1

a I a I a

1

a

1

a

1

I ⁰ ⁰ ^t ^I ^t

1

t I t I t I t

1

t I

1

^a

1

a

1

^a

1

a

1

a I a

1

a

1

I

1

I I I I

1 1 1

I I I

1 1 1 1

I

1_1---1---1---1---1---1_1_1_1

Control characters

Some ASCII codes are non-printing and have special uses Multiple names are sometimes confusing

X-OFF, DC3, Control-S, ~S, \023 X-ON, DC1, Control-Q, ~Q, \021

F86 Page 1-3

(5)

ESC, Control-[, A[, \033 LF, NL, Control-J, AJ , \012 CR, Control-M, AM, \015 BS, Control-H, AH, \010

Formfeed, NP, Control=L, AL, \014 PAD, DEL, Rub out , \177

NUL, Control-@, A@, Control-SP, ASp, \000 BREAK (QUIT) is not an ASCII character

I BREAK is a line condition discussed later under RS232

(6)

ASCII Character Set Chart

Mu1tics

Bin Oct Dec Hex Def. Key/Name Other Definitions

0000000 000 0 00 NUL Contro1-@ Contro1-SP on some terminals 0000001 001 1 01 Contro1-A SOH, Start of Header

0000010 002 2 02 Contro1-B STX, Start of Text 0000011 003 3 03 Contro1-C ETX, End of Text

0000100 004 4 04 Contro1-D EOT, End of Transmission 0000101 005 5 as Contro1-E ENQ, Enquiry

0000110 006 6 06 Contro1-F ACK, Acknowledge 0000111 007 7 07 BEL Contro1-G Bell

0001000 010 8 08 BS Contro1-H Backspace 0001001 011 9 09 HT Contro1-1 Horizontal Tab

0001010 012 10 OA NL Control-J Newline, Line Feed, LF 0001011 013 11 OB VT Contro1-K Vertical Tab

0001100 014 12 OC NP Contro1-L New Page, Form Feed, FF 0001101 015 13 OD CR Contro1-M Carriage Return

0001110 016 14 OE RRS Control-N Red Ribbon Shift, SO, Shift Out 0001111 017 15 OF BRS Contro1-0 Black Ribbon Shift,SI, Shift In 0010000 020 16 10 Contro1-P DLE, Data Link Escape

0010001 021 17 11 Contro1-Q DC1, X-ON

0010010 022 18 12 Contro1-R DC2

0010011 023 19 13 Contro1-S DC3, X-OFF

0010100 024 20 14 Contro1-T DC4

0010101 025 21 15 Contro1-U NAK, Negative Acknowledge 0010110 026 22 16 Contro1-V SYN, Synchronous Idle

0010111 027 23 17 Contro1-W ETB, End of Transmission Block 0011000 030 24 18 Contro1-X CAN, Cancel

0011001 031 25 19 Contro1-Y ^FM--, End of Medium

0011010 032 26 1A Contro1-Z SUB

0011011 033 27 1B ESC, Contro1-[ Escape, A1t-mode 0011100 034 28 1C Contro1-\ FS, File Separator 0011101 035 29 1D Contro1- ] GS, Group Separator 0011110 036 30 IE Control-A RS, Record Separator 0011111 037 31 IF Contro1- US, Unit Separator 0100000 040 32 20 SP blank Space

0100001 041 33 21 exclamation point 0100010 042 34 22 ⁿ double quote 0100011 35 35 23 # number sign 0100100 044 36 24 $ dollar sign 0100101 045 37 25 % percent 0100110 046 38 26 & ampersand 0100111 047 39 27 acute accent 0101000 050 40 28 ( left parenthesis 0101001 051 41 29 ⁾ right parenthesis 0101010 052 42 2A

*

^asterisk

0101011 053 43 2B + plus 0101100 054 44 2C comma 0101101 055 45 2D minus 0101110 056 46 2E period 0101111 057 47 2F / right slash

(7)

0110000 060 48 30

a

⁰

0110001 061 49 31 1 1 0110010 062 50 32 2 2 0110011 063 51 33 3 3

('\'1('\1('\('\

064 ^I:;t) ^'l!. 4 4

V.1...1..V.1..VV .J~ J""'r

0110101 065 53 35 S 5 0110110 066 54 36 6 6 0110111 067 55 37 7 7 0111000 070 56 38 8 8 0111001 071 57 39 9 9 0111010 072 58 3A colon 0111011 073 59 3B semicolon 0111100 074 60 3C < less than 0111101 075 61 3D equals

0111110 076 62 3E > greater than 0111111 077 63 3F ? question mark 1000000 100 64 40 @ commercial at 1000001 101 65 41 A Capital A 1000010 102 66 42 B Capital B 1000011 103 67 43 C Capital C 1000100 104 68 44 D Capital D 1000101 105 69 45 E Capital E 1000110 106 70 46 F Capital F 1000111 107 71 47 G Capital G 1001000 110 72 48 H Capital H 1001001 I I I 73 49 I Capital I 1001010 112 74 4A J Capital J

1001011 113 75 4B K Capital K 1001100 114 76 4C L Capital L 1001101 115 77 4D M Capital M 1001110 116 78 4E N Capital N 1001111 117 79 4F 0 Capital 0 1010000 120 80 50 P Capital P 1010001 121 81 51 Q Capital Q 1010010 122 82 52 R Capital R 1010011 123 83 53 S Capital S 1010100 124 84 54 T Capital T 1010101 125 85 55 U Capital U 1010110 126 86 56 V Capital V 1010111 127 87 57 'W' Capital 'W'

1011000 130 88 58 X Capital X 1011001 131 89 59 ^y Capital Y 1011010 132 90 SA Z Capital Z 1011011 133 91 5B [ left bracket 1011100 134 92 5C

\

back slash 1011101 135 93 5D ] right bracket 1011110 136 94 5E ^A circumflex 1011111 137 95 SF

-

underline 1100000 140 96 60 ^\ grave accent 1100001 141 97 61 a small a 1100010 142 98 62 b small b 1100011 143 99 63 c small c 1100100 144 100 64 d small d 1100101 145 101 65 e small e

(8)

1100110 146 102 66 f small f 1100111 147 103 67 g small g 1101000 150 104 68 h small h 1101001 151 105 69 i small i 1101010 152 106 6A j small j 1101011 153 107 6B k small k 1101100 154 108 6C 1 small 1 1101101 155 109 6D m small m 1101110 156 110 6E n small n 1101111 157 111 6F 0 small 0

1110000 160 112 70 _P small p 1110001 161 113 71 q small q 1110010 162 114 72 r small r 1110011 163 115 73 s small s 1110100 164 116 74 t small t 1110101 165 117 75 u small u 1110110 166 118 76 v small v 1110111 167 119 77 w small w

1111000 170 120 78 x small x 1111001 171 121 79 _Y small y 1111010 172 122 7A z small z

1111011 173 123 7B left brace 1111100 174 124 7C vertical bar 1111101 175 125 7D right brace 1111110 176 126 7E tilde

1111111 177 127 7F PAD DEL Rub out

MCS Overview F86 Page

(9)

Baud Rate

Discrete signal events transmitted per second Usually but net equal to bits per second

I New 2400 bps modems are 1200 baud Line protocol

Parameters of a line that user can't change

Parameters that user can change are called terminal protocol A line can have several levels of protocols that:

MCS Overview

Synchronise data transmission and reception

Ensure correct and comp1ete.reception of data by flow control and acknowlegement of received data.

Multiplex data for different devices on single line

F86 Page 1-8

(10)

I ASYNCHRONOUS I

i I I

! !

I I

KERMIT XMODEM

Communications Protocols Supported by Multics

SERIAL BINARY I

I

I BISYNC I

I I I

I

SYNCHRONOUS I i

I I I HDLC I

I I I

I / Synchronisation I of Clocks

i and Data

\

I /

I I Reliability

GllS I of data (flow I I control &

I I acknowledge)

I \

---

I

,---c

I I I I I I I I

I I I I I I I I /

3270 HASP 2780 3780 X.2S

Q)IL (U~ ~1{

f\<;,\'~5

RCI VIP POLLED I Multiplexing

I ('.(bItS

l

^VIP ^\ ^, ^I^~

"'" l '\. f I ~ ~ ~ S ⁴^v(Y^{P, ,} J'i ^{At (} J~ ~ '"' . ^1\/j ./

J ..

v~~~"> ~fIVL ^\

e..

'3 :l ( b

\ Ql"..: "

(11)

Asynchronous Protocols

Data comes in bit by bit as changing signal on a wire with one voltage to represent logic 0 and another to represent logic 1 Two things need to be synchronized between the sender and the receiver:

When to sample each bit (synchronising clocks)

Which bit is the first in data (first in each character) Asynchronous protocols resynchronize both for each character

MCS Overview

Start bit used to signal beginning of first bit of character I Transition from idle state (logic 1) to start bit (logic 0) One or two stop bits used to put line in idle state at end of each character

10 bits used to send 1 character, so BPS - 10 CPS, efficiency 70%

F86 Page 1-10

(12)

Asynchronous Protocol Problem: Synchronisation of clocks and of data start

"6" = 066 octal = 0110110 binary = 00110110 with even parity At 300 baud, 1/300 sends between bits.

Bits sent to send ASCII "6"

----> Message Flow ---->

P D6 DS D4 D3 D2 D1 DO

o

0 1 1 0 1 1 0

A A A A A A A A

I I I ! I I I I

I ¹ I ¹ I ¹ I ¹ I ¹ I ¹ 1 1 I

1 ---I ---I ^---I ---I ---I ---I ^---I I ³⁰⁰1 300₁ 3001 300₁ 3001 300 1 3001

1 I I I 1 I I 1

P D6 DS D4 D3 D2 D1 DO

Sampling needed every 1/300 second to read received bits,

(13)

Asnynchronous Protocol

Bits sent to send ASCII "6"

----> Message Flow ~--->

Idle IStopl P D6 DS D4 D3 D2 Dl DO IStrtl Idle

o

0 1 1 0 1 1 0

"- "- "- "- "- "- "- "- ....

I I

I I I I

I 1

I

¹

I

1

I

1

I

1

I

1

I

1

I

1

I

³

I ---I ---I

^-~-I

- --I

-=-1 ^--~I

- --I I

^{3001 300}1 3001 300 1 3001 3001 300 1 600

I

I I I I

I

I I

P D6 DS D4 D3 D2 Dl DO See

Transition

(14)

Asynchronous throughput

... 1 1 100 110 1 100 100 1 101 100 1 1 ...

I I S P D D D D D DDS S P D D D D D DDS I I d d t a a a a a a a a t t a a a a a a a a t d d 110 r t t t t t t t a o r t t t t t t t a l 1 e e p i a a a a a a a r p i a a a a a a a r e e

t t t t

Y Y

1 parity bit 1 start bit 1 stop bit 7 data bits 3 overhead bits Maximum throughput: 70%

F86 1-13

(15)

In Multics, maximum speed for asynchronous lines is 19,200 bps Protocol used by typical asynchronous terminals is called ASCII

I Could be used by non-ASCII, e.g. EBCDIC, terminals Multics used to support other asynchronous protocols

2741 1050

ARDS

Standard asynchronous connections provide no guarantee of reliability The Kermit and XMODEM protocols sit on top of the asynchronous

protocol

They provide flow control, error detection, acknowledgement, for the purposes of reliable file transfer

Synchronous Protocols

Again, need to synchronize clocks and data Clocks are synchronized by extra signal Data synchronization is per-block

Two or more SYN(characters are sent to indicate start of block

Typical synchronous protocol adds information at beginning and end of each block

Block length, checksum, etc.

Typical synchronous protocol requires acknowledgement of each block from receiver

Throughput depends on details of protocol, but is higher than asynchronous for medium to high volumes of data

(16)

Typical Synchronous Protocol

I ^S ^S ^{H ... R} ^D ^{D ... D} ^DI ^{T ... T} I ^y ^y ^{D ... D} ^A ^{A ... A} ^A I ^{R ... R} Idle ₁N N R ... R T T ... T T I ^{A ... A}

---1

^A ^{A ... A} ^A 1 I ... I

I 1 ^{L ... L}

I I ^{E ... E}

I ^{R ... R}

---

<-Sync-> <-Hdr-> <---Data---> <-Trl->

Typical

Values: 2

100 data bytes

2 100

2 Sync bytes 2 Header bytes 2 Trailer bytes 8 Overhead bytes Throughput: 100/108 = 93%

2

I I

I ^Idle

1- ... _--- 1

I I

(17)

S

"irVl'h (o'"'oS

In Multics, maximum speed for asynshrea&Us lines is 72 KB Multics supports a variety of synchronous protocols:

HASP I 2780/3780

3270 GllS VIP

Polled VIP HDLC

Xo2S Multiplexer

There are many ways to have several logical connections over a single physical connection

This is known as a multiplexed line

For some types of multiplexed lines Mes can perform the work of multiplexing/demultiplexing the logical connections

The idea of mUltiplexing is generalized in MCS to include an arbitrary number of levels of mUltiplexing

MCS considers the FNP to be a multiplexer because it has many

channels connected to it and mUltiplexes all of that information over a single physical connection (the DIA)

Modem

MOdulator/DEModulator

Allows data to be transmitted over phone lines Many different standards for modems

Modems may be full or half duplex Not to be confused with echoplex RS232jV24

Mes Overview F86 Page 1-16

(18)

Defines connection between

Data Terminal Equipment (DTE): Terminal or computer Data Circuit-terminating Equipment (DCE): Modems Connection is by 25 pin connectors and cables

Diagram shows the pins used by Multics in asynchronous connections Synchronous connection also uses pin 24 for timing (clock signal) Used for all Multics protocols except HDLC

1

^I ^V\..^{f! -}

j;

^{v 1-.5}^{1 ()}^y\

fre(;- J ~

^VI

~

⁽

~

^Y)

~' ".~, ^I

J,

-/c....\ ~}.(~f - VlIVCS(Cv\

Standard Commurtications Concepts

Mes

^Overview F86 Page 1-17

(19)

Phone

DTE RS232 DCE lines DCE RS232 DTE

I I ^I I

I I

I v _I

V 1 ^V 1

Terminal

1---1

^Modem ^Modem 1---1 ^Computer

I I I 1

CClTT Circuit

Pin No. Name Nom Description Description

1 101 GND TP Ground Terre de protection

7 102 GND TS Ground Terre de signalisation

2 --> 103 TX ED Transmission Emission de donnees 3 <-~ 104 RX. RD

\t'~P- ~ 'fO'<I~ ^{_ _}> ₁₀₅ _RTS _DPE

""o~

....

⁵^<_^~ 106 CTS PAE

",J, ____

6 <=_ ₁₀₇ _DSR _PDP

~J~

...

8 <== ¹⁰⁹ ^CD ^DP

Reception Reception des donnees Request to send' Demande pour emettre Clear to send Pret a emettre

Dataset ready Poste de donne pret Carrier Detect Detection de 1a porteuse ,\'?e.""·,..,{20 --> 108 DTR CPD Data terminal ready Connectez 1e poste de donnees

MALE

\ /

\ 1 2 3 4 5 6 7 8 9 10 11 12 13 /

\ /

\ 14 15 16 17 18 19 20 21 22 23 24 25 /

\~---~/

FEMALE

\

/

\ 13 12 11 10 9 8 7 6 5 4 3 2 1 /

\ ^/

\ 25 24 23 22 21 20 19 18 17 16 15 14 /

\---~/

(20)

Modem Dialup Sequence

TTY Modem Modem FNP

DTE DCE DCE DTE

g (TX) 2

--->

² ²

<---

² ^(TX) ^f

f ^(RX) ³

<---

³ ³

--->

³ ^(RX) ^g

c (RTS) 4

--->

⁴ ⁴

<---

⁴ ^(RTS) ^b

e (CTS) 5

<---

⁵ ⁵

--->

⁵ ^(CTS) ^e

d (DSR) 6

<---

⁶ ⁶

--->

⁶ ^(DSR) ^a

e (CD) ⁸

<---

⁸ ⁸

--->

⁸ ^(CD) ^e

c (DTR) 20

--->

²⁰ ²⁰

<---

²⁰ ^(DTR) ^b

To listen to a line, the FNP raises RTS (pin 4) and DTR (pin 20) and then waits for CTS (pin 5), DSR (pin 6) and CD (pin 8) to go high.

The FNP detects a hangup if DSR (pin 6) or CD (pin 8) drop for more than one second. If CTS (pin 5) drops, the FNP suspends output.

Scenario:

a) Modem on FNP is powered on.

r"

^{1 ,.,}S. O,t R.

b) FNP boots and listens to the line. (~:US ~1$ 0)(

c) The terminal is turned on. ~~hl"s r1',{ f.l'TR.

d) The terminal's modem is turned on. Il""':

s.,

⁰¹^~

e) The telephone call is made and the modems are connected. f'~;SN ~')j

en)

f) Multics sends the login banner.

g) User types login line.

1

'i ~

~~ S

^Or,t"

f'l S .... ~

^{1-\ {}

~ j

^v{Jl/^j^{- l} ^{/ '}^f""1'5 ,.;, r

1'-t,1

^f ⁽⁾^I

OS~ -

(on" t,"'hof'\

€.sJl.,bJ:5~!

(.1 5 - f- (

0"" «(} '" ~ro ^{, ,,)}

r :

~

J. '\

6

aT

~

(21)

Break/Interrupt

Out-of-band signal

Logic 0 on pin 2 for 100 to 600 Line Driver

Also known as short-haul modems or point-to-point modems

Inexpensive replacement for modems for point-to-point connections No real standards

Direct Connect

For very short distances, a direct RS232 connection is possible Very inexpensive replacement for modems

Theoretically limited to about 50'

I

Practically can be extended much further

Known as hardwired connection, null modem, modem bypass Each DTE must be made to think it is connected to a DCE

MCS Overview ^F86 Page 1-20

(22)

(PG)

TTY DTE

1

6-WIRE DIRECT CONNECT

FNP

DTE 1 (SG) 7 --- 7 (TX) 2 ---\ /--- 2

\

(RX) 3 ---/ \--- 3

(RTS) (CTS)

4

--I

I

5 --I

1-- 4

1--

1 ⁵

(DSR) 6 - -1 I ~ - 6

I 1

(CD) 8

--1----\ /----1--

8 (DTR) 20 ---/ \--- 20 \

TTY FNP

DTE DTE

(PG) 1 1

(SG) 7 --- 7

(TX) 2

---\

/--- 2

\

(RX) 3 ---/ \--- 3

(RTS) 4 --I 1 - - 4

1 1

(CTS) 5

- - i

I - - ⁵

(DSR) 6 i - j - - 6

1 1

(CD) 8 --1----\

/----1--

⁸

\

(DTR) 20 ---/ ^\~~~~-~~^L.V^')()

(23)

Direct-Connect Dialup Sequence

TTY FNP

DTE DTE

d (TX) 2 ---\ /--- 2 (TX) d

c (RX.) 3 =---/ \ \----=~- 3 (RX) c

b (RTS) 4

- -I

1- - ⁴ ^(RTS) ^a

I

b (CTS) 5 --I J -- 5 (CTS) a

a (DSR) 6 ! 1-- ⁶ ^(DSR) ^b

1 1

a (CD) 8

--1----\ /----1--

⁸ ^(CD) ^b

b (DTR) 20 ----=--/ \---

\

20 (DTR) a

Scenario:

a) FNP boots and listens to the line.

b) The terminal is turned on.

c) Multics sends the login banner.

d) User types login line.

TTY FNP

DTE DTE

(PG) 1 1

(SG) 7 ---~- 7 (TX) 2 ---\

/---

²

\

(RX) 3 ---/ \--- 3

(RTS) 4 - -I I - - ⁴

1 I

(CTS) 5 - -I 1-- ⁵

(DSR) 6 _{- - 1}

I

1-- ⁶

1 I

(CD) 8 --I

/----1--

⁸

(DTR) 20 ====---/ / 20

(24)

Line Monitor

Monitor RS232 signals and display transmitted and received data Breakout Box

Monitor RS232 signals Also known as a Blue Box.

Line Monitors, Blue Boxes

DTE RS232 DCE I V I I

Terminal 1-+ +-1 Modem

Phone lines

I

V

DCE RS232 DTE I

I V I

Modem I -+ +-I Computer

_ _ _ _ I I 1 1 _ _ _ _ _ _ _ _ I I I 1 _ _ _ _

_ I _ I -

I

Blue Box/I I Line Mon. I

I I

_ I _ I - I Blue Box/I I Line Mon. I

I I

(25)

~ Standard Multics Concepts Ring 0 Supervisor

wllen a process requires supervisor services, it executes supervisor programs

Three ways to enter supervisor code:

Call

Fault

Explicit request for supervisor services

For example, create a segment, make a segment known. write data to a terminal, read input from a terminal, etc.

Faults are caused by conditions within the CPU Implicit request for supervisor services

For example, page faults, segment faults, linkage faults Interrupt

Interrupts are caused by conditions outside the CPU Perform a service for another process

For example, handle completion of a disk read, interrupt from FNP, etc.

Initializer/Answering Service

The Initializer process has a number of tasks to perform Listen to login lines

Execute operator commands Load FNPs, other multiplexers Etc.

BlockjWakeup

Mechanism used to wait for events of unknown duration Terminal I/O, tape I/O

Process is in user ring while blocked

Standard Multics Concepts

Mes

^Overview ^F86 Page 1-24

(26)

When event occurs, some other process sends a wakeup to blocked process

Compare with WaitjNotify, to wait for events of short duration Disk I/O, system locks

Process is in ring 0 while waiting

When event occurs, some other process notifies waiting process by changing its Traffic Control state

Standard Multics Concepts

(27)

"& MCS Parts

FNP

Ring 0 Ring 4

MCS Overview

MCS Parts

F86 Page 1-26

(28)

Central System (CS) Multics Host

Direct Interface Adapter

355

Communica- tion lines Communica- tion Devices

1

I

RING 4

hcs

RING 0

1

I

DIA I I D~ (('c1

I I

_ _ 1 ___ 1 _ -

I FNP

I 1 ______________ _

term mpx term /

\

term term

MCS Parts

I/O Modules, e.g. tty_

Block/Wakeup PL/I: >sll, >sss Answering Service FNP loading, dumping PL/I: >tools

Data conversion, translation

Manage wired buffer space TI,/,.JluF Communicate with FNP

Handle FNP interrupts

De-multiplexing Un 0)4(1{' $,51''''''5 /on(/ ell 'ffllf_J ~I sLo,l). 6 PL/I & ALM: Hardcore (MST)

\",,(Jf'F-aCf

cA..iCtf'ler

t;... 'tc. ·Vo..'1}f~r

Transfer of data over DIA I nfP((v,fJ" ~ Buffer space management ,.

'r/ _ B

u'::;"

Echoing

P dd · ^I

J I

I ... R,."", ~ o."V Moif a ^~ng J4'"P{'''!) "'1;/(5 f6/ eo..YSjrJ()"~· ;..J

Flow control fo r- A-~'1"'c.. X ^0'" ⁾⁽(')f!~

Tell CS state of channels Send terminal input to CS

Send output from CS to terminal Modem control (RS-232, e.g.) Interval timers

Format, interpret synchronous msgs MAP355: loaded from Multics into FNP

'V",ss,,...t31

i

11i'-1-9\.otl9e.

MCS Parts

F86 Page 1-27

(29)

The Ring 0 and FNP parts of Mes are covered in this course

The Mes functions made available to the user by Ring 0 and the FNP will be explained using the tty_ I/O module as an example

Following diagram shows the relationships of the various I/O modules for terminal I/O

tty_ uses the same hcs interface as other I/O modules, and therefore makes ^a good example

I/O Module Dependencies

+-~~-- hasp_workstation_ <--~---+

+---

hasp_host_ <--~-~---+ I

+--- ibm3270 I

I

remote_input_

+--ibm2780~3780_

<--+----

remote_punch_

+---

bisync_

<----+

I remote_teleprinter_

hcs

<---+ +---+

remote_printer_

+---

gl1S

<---+

+---

^tty_<---+-~---+ I

+---

tc io

+---

I kermit

+--- emacs

+---

xmodem io

Mes Parts

Mes Overview F86 Page 1-28

(30)

a FNP Hardware Description

Up to 8 FNPs can be configured Names

FNP

Front-End Network Processor Front End

Fuh-Nup Datanet DN355 355 6670 6678 l8x FEP MPX Model Numbers

355

6632

6670

MCS Overview

The original Multics FNP

Has given its name to many of the MCS programs Limited to 32K memory

No longer supported as of MRll

A newer version of the 355 Limited to 32K memory

No longer supported as of MRll

Level-6 based, emulates 355

FNP Hardware Description

F86 Page 1-29

(31)

Up to 256K memory with extended memory addressing Two models

6678 with cache memo~j

6651 without cache Architecture

Has same basic architecture as Multics: 10M, SCU+MEM, CPU Peripherals connected to 10M

DIA HSLAs

FNP Architecture

Multics

+---+ +---+ +---+

CPU +---+ SCU +---+ 10M +---DIA----

1+---+1 1 I

IIMEMIl

I I

\+---+\

I \

+---+

^+---+ ^+---+

FNP 10M Channels:

0 FNP Console 1 FNP Reader 2 FNP printer 3

4 DIA 5 ^e^'fifA0: ^0...

6 HSLA 0 7 HSLA 1 8 HSLA 2

9-14 LSLAs ^{o~5o\~' ~} 15 Clock

+---+

FNP

+---+ +---+ +---+

-+ 10M +--+ SCU +--+ CPU

\ 1+---+\ \

\ \ IMEM\ I I 1 1+---+1 1 +-+-+-+ +---+ +---+

I +---+

+-+----+ +--+---+

1 HSLA I \ HSLA I

+-+-+-++ +-+-+-++

+---+-+-+----+-+-+---+

I I I \

1 I 1 1 Terminals

(32)

Data and Instruction Formats l8-bit words

I/O commands also know about 36-bit words

F86 Page 1-31

(33)

STORE REFERENCE INSTRUCTION FORMAT

0 0 0 0 0 0 1

0_1_2_3 _ _ 8_9 _ _ _ _ 7

I I I I

IIITAGIOpcodel Delta

1_1_1 1 _ _ _ _

1 2 6 9

INDEX REGISTER (Xn) -- UNPAGED ADDRESS

0 0 0 1

o

2 3 _ _ _ _ _ _ _ _ 7

1 I I

ITAGI Address I

I_I I

3 15

INDEX REGISTER (Xn) PAGED ADDRESS

0 0 0 0 1 1

0 2 3 9 0 7

I I I I

ITAGIPage No. I Offset I

I_I I I

3 7 8

Mes

Overview F86 Page 1-32

(34)

ACCUMULATOR REGISTER (A)

°

0 ___________________ 7 ¹

I I

I ^A I

I I

18

QUOTIENT REGISTER (Q)

°

0 ____________________ 7 ¹

I I

I Q I

I I

18

ACCUMULATOR-QUOTIENT REGISTER (AQ)

°

^{1 1} ³

°

_I ^{7 8}_I ⁵_I

I Even Word (A) I ^{Odd Word} ^(Q) I

I I I

18 18

MCS Overview ^F86 Page 1-33

(35)

Extended Memory Addressing

So-called paging is used to address beyond 32K

Difficult to program, so only certain t)~es of data are stored in extended memory

No programs in extended memory

\\is

\

'}~i ^I'

~---~

S

(36)

FNP Extended Memory Addressing

Memory

+---+

+--->+

000000-000377 Page 0 I

I

+---+

I

+--->+

000400-000777 Page 1 I I

I I

I i

+---+

I I

+--->+

001000-001377 Page 2 Page Table I I I

+---+

^{I I I}

4000 I

A=O+- ---+

^{I I}

+---+

^{I I}

4001 I

A=O+---+

^I

+---+

^I

4002 I

A=O+---+

+---+

!

I I

+---+

I'

+--->+

076400-076777

I I Page 175

+---+

I

+---+

4175 I

A=O+---+

+---+

4176

A=l+---+

+---+

4177

A=l+---+

+---+

077000-077377 Page 176

+---+

077400-077777 Page 177, end of 32K

+---+

100000-100377

Page 200, start extended mem

+---+

+--->+

100400-100777 Page 201

MCS Overview

+---+

+--->+

177000-177377 Page 376

+---+

177400-177777 Page 377, end of 64K

+---+

F86 Page 1-35

(37)

FNP Address Calculation Example 1

Reference To Address In Low-Order Memory Using Non-Paged Addressing c (x2)=076700; c(x3)-077240;

~ c(47S)=004000; c(417S)=000000;

'\. "

'7 ~\ Ii.e S. .... -Icl^J(,! s.~

er .po,~"(l ",\",131~

I

+---=-=--====---~-==---=--~~---+

2 0 7 0 0 1

010 000 III 000 000 001 I I

000000001

y{

001 -- I

c(4176)=133040

+---+

+---=---=---~---+

\ / \ / Final Address

I 1 _ _ _ _ _ _ +- - - -= - - - ---+

1 0 7 6 7 0 1

V

+--==---=---+

+---+ I

I X-register 2 I

+---+ I

1 0 I 7 6 7 0 0 I

I I I

I 000

i

III 110 III 000 000 I

+--==---=---=---+ I

I Tag I IS-bit address I I

1 I 1---=-==--=--

i

a

I 76700 I

+---~-=----+

(38)

FNP Address Calculation Example 1

Reference To Address In Low-Order Memory Using Paged Addressing

c (x2)=076700; c(x3)=077240; c(475)=004000; c(4l75)=000000; c(4l76)=133040

+---+

Instruction: Ida 1,2

+---+

2

a

7

a a

1 1

1 I 1 I 1 1 I

1 010 I 000 I III 1 000 1 000 1 001 1

+---+

I ITag Opcode Delta

1 I I I

I 0 I 10 I 000111 I 000000001

I I ! I

I 0 1 2 I 07 I 001

+---~---+

+---+

\ / Final Address

\ /

I ¹

- - - - +---+

I

V

0 7 6 7 0 1

+---+

I

X-register 2 I

+---+

I

1 0 7 ^I 6 7

a a

^I

1 I I I I I I

I 000 III I 110 I III I 000 I 000 I i

+---

---+

^I

I Tag IS-bit address I I

I 1---

, 0 76700 I

+---

---+

Tag Page No. Offset

000 III 110 1 11 000 000

o 175 300

+---

---+

\ /

1

V

+---+

Page table entry @ 4175 [c(475) + 175 -> 4176]

+---+

o

0 0 0 0 0

000 000 000 000 000 000

+---+

1 Page addr mod 2561 IActl

I I I I

I 000 000 000

a

I 00 I

a

i 00000

+---+

F86 Page 1-37

(39)

FNP Address Calculation Example 3 Reference To Address In Extended Memory

c (x2)-076700; c(x3)=077240; c(475)~004000; c(4l75)=000000; c(4176)=133040

+---+

Instruction: Ida 113

+---== ---=-=---=-+

3 I

a

7

a a

1 I

I I I I I I

I all I 000 I III 000 I 000 I 001 I

+--- ---+

I ITag Opcode Delta

I I

I 0 I 11 I 000111 000000001

I I I

I a I 3 I 07 001

+--- ---+ +---+

\ / \ / Final Address

I 1 _ _ _ _ _

+- ---+

V 1 1 3 I 3 2 4 1

+---+ +---+

I X-register 3

+---

---+

I 0 7 I 7 2 141

a

I I I I I I

I 000 III I III I 010 I 100 I 000 I

+--- ---+

I Tag IS-bit address

I I a 77240

+--- ---+ +--- ---+

1 Tag Page No. Offset 1 3

I

3 2 4 a

I

I I 1 1 1 I I

I 000 III III a 10 100 000 1 001 I all I all 010 1 100 1 000 I

I

+--- ---+

I 0 176 240 1 001 011 all a 10 100 000

+--- ---+ +---+

\

/

\

/ /

V I ______________ ~/

+---+

I Page table entry @ 4176 1 [c(475) + 176 -> 4176]

+---+

1 3 3 0 1 4 0

1 1 1 1 1 I 1

I 001 I 011 I 011 I 000 1 100 I 000 1

+---+

1 Page addr mod 2561 IActl

I I 1 I 1

I

001 all all a

I

00 1 1

I

00000

I

+---+

---\ /---

1---

(40)

HSLA

I High-Speed Line Adapter Emulated in 6670s

All communications lines are connected to HSLAs Maximum of 32 channels per HSLA

Maximum of 3 HSLAs per FNP => maximum of 96 channels per FNP

HSLAs do much of the work of running a channel, freeing up the FNP's CPU

Set and detect RS232 signals

Interrupt FNP when a signal changes Read incoming characters into a buffer

Interrupt FNP when action is required Buffer full

BREAK condition

Interesting character (such as CR, LF, EDT) read

Character Control Table (CCT) tells HSLA what characters are interesting

Does not do echoing

Send buffer of characters to terminal Interrupt FNP when finished

Old FNPs had HSLAs and LSLAs (Low-Speed Line Adapters) Channel names

One component for each level of multiplexing FNP. H/L 99

b.hlOI

FNP . H/L 99 . SUB I a.h006.prtl Mother/Daughter Boards

(41)

HSLAs are emulated by Mother and Daughter Boards Communications lines are connected to daughter boards

Two lines are connected to each daughter board

There are different types of daughter boards for different types of lines

Asynchronous Autocal1 channels BSC

I GllS

---

HOLC daughter boards only have one line connected instead of two Daughter boards are properly known as CLAs

I Communications Line Adapter

Daughter boards are mounted on mother boards

MCS Overview

Four daughter boards can be mounted on one mother board Maximum combined speed of lines on mother board is 72KB An FNP can have up to 16 mother boards

12 mother boards 4 daughter boards 2 lines => 96 lines per FNP 4 mother boards are the equivalent of an HSLA (32 lines)

Mother boards are properly known as HMLCs High-speed multi-line controller

~ I~los\

fV'

~ ^0(·'1'

i

6 n

~

aSS', ()\ "

\-0 \ ~\o(f

^J

rYl'O

T

hr; r

~:ro", {'~

^,

^.5

(I6'l (Or'\.

c

¹

.)5)

v~

.

F86 Page 1-40

(42)

Mother/Daughter Boards

la.h23l a.h2301 la.h229 a.h2281 la.h227 a.h2261 la.h225 a. h224 1

I CIA I I CIA I I CIA I I CIA I

_I

OA,J~lil"f ~~_I

I_I I_I 1_

: HMLC

Mf!lJ{..~r ~r;.4,rf

1 ______________________________________________________ __

la.hl07 a.hl061 la.hl05 a.hl041 la.hl03 a.hl021 la.hlOl a.hlOOI

I CIA I I CIA I I CIA I I CIA I

_I I_I I_I I_I I_

I I

I HMLC I

I I

la.h03l a.h0301 la.h029 a.h0281 la.h027 a.h0261 la.h025 a.h0241

I CIA I I CIA I I CIA 1 I CIA I

_I I_I I_I I_I I_

I I

I HMLC I

I I

la.h023 a.h0221 la.h02l a.h0201 la.h019 a.h0181 la.h017 a.h0161

I CLA I I CIA I I CLA I I . CIA I

_I I_I I_I I_I I_

I I HMLC

1---

la.h015 a.h0141 la.h013 a.h0121 la.hOll a.hOlOI la.h009 a.h0081

I CLA I I CIA I I CIA I I CIA I

_I I_I I_I I_I I_

I

HMLC I

---~---I

I I

la.h007 a.h0061 la.h005 a.h0041 la.h003 a.h0021 la.hOOl a.hOOOI

I CL~ I ^CIA ÎI I Î ^CLA ÎI I Î Î"'T^v.un.^1\ ÎI

_I 1_1 _ _ _ _ _ I_I I_I I-

HMLC

1---

o HMLC ⁼ Mother Board o CIA = Daughter Board

I I I

(43)

DIA

Direct Interface Adapter

Connects Multics IOH to FNP 'T " " ,

.l.V.I.'l

200KBit/sec smart controller DIA can:

Send interrupts in both directions

Transfer data between memories of FNP and Multics at request of either

MCS does not use all these possibilities, i.e. FNP initiates all data transfers

Can have 2 DIAs per FNP

I

But Multics will view each OIA as a separate FNP

(44)

a MCS Manuals

AN8S: Communication System SDN

MCS Internals, both Ring 0 and FNP

Theoretically unavailable: last upc~te MR7.0 CC7S: Multics Administrators' Manual--.Commu:t.:.1ca~ions

AG93: Multics Subroutines and Input/Outptlt Modules' AG9l: Multics Programmer's Reference Guide

TTF described in Appendix B

Input conversion rules explained in Ch2pter 3 AN87: Hardware and Software Formats PLM

Theoretically obsolete and Unavailable Chapter 6 has FNP dat~ formats

DDOl: DN3SS/6600 Macro Assembler Program FIV&'\

MeS Manuals

MCS Overview

t.at

^Page^1-43

(45)

MCS Administration

& eMF/CDT

Channel Definition Table

CDT describes all configured FNPs, multiplexers, lines Created from ASCII source file Channel Master File An Answering Service Database

Stored in >scl>cdt

Used by Initializer to manage lines, logins, etc.

Used to initialize Ring 0 databases at Multics bootload Ring 0 Databases are not stored permanently

Used to initialize FNP databases at FNP bootload

CMF/CDT

MCS Administration F86 Page 2-1

(46)

Spare_channel_count: 10;

Sample CMF Altows 'fOv '\ 0

cr.J~

FNP_required_up_time: 5;

' \ ~9",\~>

a.\s.o \ ()

\C,"VE'f \~wc\

" - - tb~\~ ~o>S· ~\'\ ~ ~ \t>~.(.

yv.,v h';~h"Q{' t (c,.~ \ ~ \. ~ ~~

Check acs: all;

FNP: ^a·_, _D\S_'f ^,

V\ ( \-.. \ . t' ~

type:

lsla:

hsla:

DN6670; \ (;, \Jb\ p,,~ to \<~~f ^j'T 0.

0; 1'\0 \> CA. ,0

3;

memory: 64;

image: >sldd>mcs>info>fnp_a;

service:

name:

baud:

active;

a.cOOO;

9600;

service: slave;

name:

baud:

a.hOOO;

1200;

service: mc;

name:

baud:

a.hOOl;

1200;

service: login;

baud: 1200;

service: login;

name:

baud:

a.h003;

1200;

service: login;

comment: "COLTS executive channel";

line_type: COLTS; terminal_type: none;

comment: "console pupitre";

line_type: ASCII; terminal_type: ROSY;

attributes: hardwired,dont_read_answerback;

comment: "console datanet";

line_type: ASCII; terminal_type: ROSY;

comment: "AJ5l0 dans salle de consoles 125";

line_type: ASCII; terminal_type: AJ510;

comment: "AJ860 dans salle de consoles 121";

line_type: ASCII; terminal_type: AJ860;

/*** a.h006 is X.25 Sync HOLC daughter. This board steals a.h007 as well. */

comment:

service:

multiplexer_type:

baud:

terminal_type:

line_type:

"X.25 canal principal 113001300";

multiplexer;

x25;

9600;

X25_TRANSPAC;

X25IAP;

service: autocall;

generic_destination: "transpac";

comment: "X.25 dial_out sub-channel";

service:

comment:

terminal_type:

MCS Administration

"X.25 login sub-channel";

ascii_crt;

CMF/CDT

F86 Page 2-2

(47)

baud:

attributes:

1200;

dont read_answerback;

baud: 4S00; line_type: BSC; terminal_type: HASP_HOST;

mUltiplexer_type: hasp;

service: multiplexer; attributes: Ahardwired;

service:

line_type:

terminal_type:

service:

. line_type:

terminal_type:

service:

line_type:

terminal_type:

service:

line_type:

terminal_type:

slave;

BSC;

HASP_HOST;

slave;

ESC;

HASP_HOST;

slave;

BSC;

HASP_HOST;

slave;

BSC;

HASP_HOST;

name:

baud:

a.hOlO;

4S00;

service: login;

comment: "Questar dans Ie bureau Adjemian-Weberl1;

line_type: ASCII; terminal_type: VIP7205;

CMF/CDT

MCS Administration FS6 Page 2-3

(48)

CMF delivered in >udd>sa>a

Global key-word

2 crashes in this time => no reload

Applies to lower-level multiplexers as well

Global keyword

Number of extra entries in ring 0 databases

Adding CDT entries for which there is no room in ring 0 databases causes problems

Other global keywords

Define default values for omitted local keywords FNP:

One FNP statement for each configured FNP Followed by information about the FNP type:

I dn6670 memory:

I Memory size in Kwords hsla:

Number of HSLAs: can always say 3

Must have one line declared on HSLA 0 before using HSLA 1 Likewise for HSLA land 2

image:

I Pathname of image to load in FNP service:

I active or inactive

CMF/CDT

(49)

name:

One name statement for each configured channel Followed by information about the channel

Can have a range of channel names, e.g. a.h006.001-a.h006.016 comment:

Comment stored in CDT

Not like /* comments */ which are ignored in CMF Important to use comments to document

Also important to have well-organized CMF baud: ~~5

Up to 19.2KB for async, 72KB for sync

110, 133, 140, 300, 600, 1200, 1800, 2400, 4800, 7200, 9600, 19200, 40800, 50000, or 72000

line_type:

fll'ft'c..

Line protocol: ASCII, Gl15, BSC, VIP, POLLED_VIP, or X25LAP Cannot be changed by user

service:

login

Loaned to process for duration of process Initializer owns all lines

slave

I mc

Loaned to existing process, returned when finished or at end of process

Requested by sending wakeup to Initializer (using dial_manager_)

Example: Used by I/O daemons to attach printers, readers, -y~tc.(6.V\: ^{, 0} o..l7J .... (..L.. }Iy_ b,~J{(

I Like slave, but for the Initializer's own use

CMF/CDT

(50)

I Used for operator terminals autocall

Like slave, but Initializer makes requested phone or network connection before loaning it

I Example: dial out .. l' n.;r""",oY\~- \ fL~\.ft.,J &t- V).tI,\e ~ AI

'c>

vseA 0\),,;- -f....:::rS

,0

(O'f'f'fJC) 0 ,-

inactive

Not listened to when FNP boots

Useful for holding a spot for a line that is not yet physically installed

multiplexer

Line is a mUltiplexer channel

mUltiplexer_type statement must be used as well multiplexer_type:

ibm3270, vip7760, hasp, x25, or sty dataset_type:

Used mostly for half-duplex-modems

Require special handling of RTS, CTS, etc.

terminal_type:

Can be changed dynamically by user

For mUltiplexer, TTF entry gives multiplexer-specific parameters in the additional info field

generic_destination:

Valid for autocall and slave lines

Allows users to attach line without knowing channel names Useful to group together channels, allow changing channel assignments without affecting users

charge:

Specifies a surcharge for using the channel

For login lines this is in addition to connect charges

CMF/CDT

F86 Page 2-6

(51)

I Must correspond to device type in installation parms check acs:

ACS Segments in >scl>rcp I E.g. >scl>rcp>a.h001.acs

Keywords specify when access checking is to be done login

slave

priv attach dial in dial out all

Default is priv_attach, dial out attributes:

hardwired

Eliminates use of the login_time parameter in installation_parms

set modes

Modes are set according to default terminal type at dialup Only attribute that is on by default

dont read answerback

System does not send ~E (ENQ) at dialup to request terminal's answerback

check answerback

I See answerback statement audit

See access class statement none

CMF/CDT

(52)

Default is

set_modes, A audit , A check_answerback , Adont_read_answerba ck,Ahardwired answerback:

Specifies expected answerback for terminal

I If check answerback attribute is set~ any other answerback will be refused connection

access class:

Specifies the AIM classes of users allowed to login on the line Enforced if the audit attribute is set

initial command:

Preaccess command (e.g. login, modes, ^ttp~etc.) to be executed at each dialup

cv cmf

Converts CMF into CDT Usually CMF.cmf -> CMF.cdt

Resulting segment has same format as >scl>cdt but with no dynamic information

install

Initializer is the maintainer of COT Sends a request to Initializer

Initializer merges dynamic info from existing COT with info from new COT

Requires access to >scl>admin acs>cdt.install.acs Adding, deleting, changing channels

Many CMF changes do not take affect immediately Some require FNP reboot to take affect

Tables 5-1 and 5-2 in CC7S explain when changes take effect Most important are adding lines and changing speed of lines

Require FNP reboot

CMF/CDT

MCS Administration ^F86 Page 2-8

(53)

Two commands for displaying information from CDT display_cdt

I Gives detailed information on CDT entries

I Gives brief information on eDT entries

reset cdt meters resets n_dialups, n_logins, dialed_up_time

CMF/CDT

(54)

CDTE at 515115360 in use:

name:

comment:

charge_type:

service_type:

current_service_type:

dim:

line_type:

terminal_type:

baud rate:

fnp_no:

flags.attributes:

event:

tra_vec:

count:

twx:

state:

current_termina1_type:

cur_line_type:

tty_id_code:

process:

next channel:

n_dia1ups:

n_logins:

dialed_up_time:

dialup_time:

recent_wakeup_count:

recent_wakeup_time:

3 (dialed) achl14

DKU7102 sur sous canal mpx trt de Paris2

o

(none) 1 (login) 1 (login) 1 (tty) 1 (ASCII) DKU7102 1200 1 (a)

hardwired,dont_read_answerback,check_acs;

000470001164407777000107 3 (wait_login_line) 1

46

5 (dialed up) AJ510

1 (ASCII) none 7777711

o

393 348 1083 hrs 02/20/84 1

02/20/84

CMF/CDT

45 mins 11 secs.

1727.4 hfh Mon 1807.9 hfh Mon

F86 Page 2-10

(55)

Values for tra_vec in display_cdt output and WP column in tty_lines output 1 wait_dialup

2 wait answerback 3 wait_login_line 4 wait_login_args 5 wait_old-password 6 wait_password 7 wait_new_password 8 wait_logout_sig 9 wait_logout 10 wait_logout_hold 11 wait detach 12

13 14 15 16 17 18 19 20 21 22 23 24 25

wait_new_proc wait remove

wait_fin_priv_attach wait dial release

- -

wait dial out

-

wait_hangup

wait_slave_request wait_greeting_msg wait delete channel

- -

wait_connect_request wait_tandd_hangup wait fin tandd attach

-

^- ^-

wait_discard_wakeups wait_before_hangup

Channel waiting for dialup.

wau

sent, waiting for reply

Greeting typed, wait for login command.

Want rest of login line

"-cpw" was specified. Wait for old password.

Waiting for password. (If "-cpw", repeat of new one.)

"-cpw" was specified. Wait for new password Channel is hooked up. Wait for logout.

A logout has been requested. Wait for process to die As above but don't hang up when it dies.

As above but ignore channel afterwards.

As above but make new process and continue.

As above but completely expunge channel.

When channel dials up, connect it to user Waiting for master process to release.

Waiting for auto call to complete

Wait for the hangup event to occur for a channel Ignore line until someone asks

Print greeting message and wait for login line

Channel deleted - mark cdte after process is destroyed logged in; awaiting request re disconnected processes when channel hangs up, proceed with t & d attachment when channel dials up, finish t & d attachment

disregard all wakeups on channel

allow output to print before hanging up

Values for state in display_cdt output and S column in tty_lines output -1 masked

1 hung

0 1 2 3 4 5 6 7

2 known 5 dialed

free hung up

listening dialed logged in logged in dialing dialed out

& proc

MCS Administration

Terminal channel is there, but masked by MCS Terminal channel is there, but dead.

Channel being "listened" to, awaiting dialup.

Channel is dialed up. This is normal state.

Values for in_use in display_cdt output and A column in tty_lines output

Entry is empty.

Entry is usable but tty is hung up.

Entry is waiting for phone call.

Entry is connected but login not complete.

Entry is logged in but no process.

Entry has a valid process.

Entry (auto_call line) is dialing Entry (auto_call line) is in use

CMF/CDT

F86 Page 2-11